The present invention relates generally to the field of folded sheet dispensers.
Dispensers for dispensing stacked folded sheets of paper towels and the like are well known in the art. Single sheet dispensers are generally desirable because they can be refilled when only partially depleted, as compared to roll product dispensers wherein changing a partially depleted roll results in significant wasted product. Stacked single sheet dispensers are also desirable because they tend to be simple devices that are not subject to jamming or failure.
A disadvantage of folded stacked sheet dispensers is that they can be overloaded or overfilled. Overfilling the dispenser can create a pressure against the stack of sheets that makes it very difficult to remove a sheet from the dispenser. For example, the pressure against the stack may prevent a xe2x80x9ctabxe2x80x9d end of the sheet from becoming accessible for a user to grasp in order to withdraw the sheet. In an overfilled condition, the stack of sheets may be wedged in the dispenser so firmly that the portion of the sheet grasped by the user simply tears instead of dispensing the sheet. Friction against the dispensing opening may be increased by overfilling the dispenser making dispensing unreliable and problematic.
U.S. Pat. No. 5,884,805 assigned to Kimberly-Clark Corporation proposes one solution for preventing overfilling of stacked folded sheet dispensers. With the dispenser according to the ""805 patent, an overfill bracket is moveably connected to the frame of the dispenser such that an over-capacity of folded sheets in the frame displaces the overfill bracket and prevents the dispenser cover from engaging the frame.
Although the ""805 patent provides one solution, there is still a need in the art for improvements in stacked folded sheet dispensers for preventing overfill conditions.
Objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
According to the present invention, a dispenser is provided for dispensing stacked folded sheets, such as paper towels, tissues, and the like. It should be appreciated, that the dispenser is not limited by its overall shape or appearance and the present invention may be incorporated into any type or configuration of folded sheet dispenser.
The dispenser includes a housing that is configured to hold a supply of stacked folded sheets in an internal storage space. The housing includes a back panel and a bottom portion and has at least one dispensing opening defined therein. The housing also includes a cover member pivotally attached to stationary components of the housing. The dispensing opening may be in the bottom portion of the housing or the cover member. The cover member is moveable between an open position wherein access is provided to the storage space for refilling the folded sheets, and a closed position wherein the cover defines a front panel of the dispenser.
An overfill prevention device is configured within the housing and is actuated by movement of the cover from the closed position to the open position. The overfill prevention device reduces the storage space for folded sheets in the housing when the cover member is moved to its open position.
In one embodiment of the invention, the overfill prevention device comprises a bottom member, such as a plate member, against which the folded sheets are stacked. The bottom member is moveably mounted within the housing and is movable from a position generally adjacent the dispensing opening in the housing when the cover member is in its closed position, to a position vertically displaced from the dispensing opening when the cover member is in its open position. A motive member, such as a mechanical cam, is configured between the cover member and the bottom member so that the bottom member is moved to its vertically displaced position upon a maintenance technician opening the cover member to refill the dispenser with stacked folded sheets.
When the technician moves the cover member to the open position and the bottom plate member is moved vertically upwards relative to the dispensing opening, a xe2x80x9cprotectivexe2x80x9d space or gap is defined between the bottom portion of the housing and the bottom plate member against which the folded sheets are stacked. This gap acts as a protective buffer. Regardless of the number of sheets stacked on the bottom member, once the cover is closed, the bottom member moves vertically downward, and the gap or buffer then becomes part of the storage space for the stacked sheets. Thus, even if the stacked sheets are overfilled by the technician, any overfill pressure is relieved once the bottom member moves vertically downward upon closing the cover member.
The bottom member has an opening therethrough that is aligned with the dispensing opening in the housing. This opening is preferably larger than the dispensing opening in the bottom portion of the housing.
The motive member, such as the mechanical cam, operatively configured between the cover member and the bottom member includes a cam surface disposed so as to contact and move the bottom member vertically upward upon opening of the cover member. The cam surface can have various shapes and configurations. For example, the cam surface may have an eccentric shape so that the bottom member is held and maintained in its vertically displaced position upon the full opening range of the cover member. In one particular embodiment of the invention, the cam member is an elongated tab having a generally semicircular end defining the cam surface that engages against and lifts the bottom member upon opening the cover member.
It may be desired that more than one cam member be provided. For example, the cover member may be pivotally attached at opposite side panels to the housing. A cam member may be disposed at each pivotal connection. Cam members are disposed generally below side portions of the bottom plate member. Upon pivotal movement of the cover member to its open position, the cam surfaces engage against the bottom of the bottom plate member and move the plate member vertically upwards.
The invention is not limited to a particular type of motive member configured between the bottom plate member and the cover member. A simple mechanical cam may be desired for its simplicity and ease of manufacture. However, other motive devices are within the scope of the invention. For example, levers, wires or cables, etc. may be utilized to move the bottom plate member upon movement of the cover member between its open and closed positions.
It should also be appreciated that the overfill prevention device according to the invention may be utilized in any configuration or style of folded sheet dispenser.
The invention will be described in greater detail below with reference to an embodiment of the invention illustrated in the figures.